Motorized rescue cars in particular used in connection with traffic accidents are equipped with hand fire extinguishers which have a relatively small contents and can be re-filled after each application by specialists only. Since rescue cars must be ready for duty at any time additional fire extinguishers must be kept in reserve. All this results in a relatively complex and uneconomical handling of the fire extinguishing equipment.
Fire departments use trucks or vans provided with large tanks filled with water which tanks can be connected via pumps with jet pipes. The addition of foam producing ingredients to the water is accomplished via a special mixing valve. This arrangement operates properly only with large quantities of water. Such quantities can not be transported with the usual rescue cars.